The long term objective of the project is to further the current understanding and development of novel cancer chemopreventive agents. The goal of this proposal is to determine the molecular mechanism of a promising class of cancer chemopreventives. Our first aim is to determine the binding mode of CDDO, a small molecule which pharmacologically inhibits the expression of iNOS and COX-2. We will generate antibodies against a CDDO-hapten, evaluate their specificity using western blot techniques, and use these antibodies to identify if CDDO forms covalent protein adducts. If CDDO adducts are identified, we will attempt to identify cognate binding proteins using traditional biochemical fractionation guided by western blot analysis and protein identification using mass spectrometry techniques. If covalent interaction is not observed, the anti-CDDO antibodies will be used in conjunction with a photoaffinity labeling technique to identify relevant interactions. The second aim is to study the structural requirements for CDDO activity by expanding the collection of CDDO-like chemopreventives using a unique approach of diversity oriented synthesis (DOS). We would like to expand the repertoire of molecules which pharmacologically knock down expression of key inflammatory enzymes iNOS and COX-2. Structural homologs of CDDO will be used as a platform for DOS. Structure activity relationships will be conducted by monitoring changes in expression of iNOS and COX-2 using Griess assay and western blot techniques. Evaluation of the activity of these structural homologs will aid in the determination of mechanisms mediating the activity of CDDO and the molecular basis of the therapeutic properties of this molecule. Successful completion of these studies will advance the development of novel chemopreventive agents that could potentially be introduced into clinical trials.